[stemlord]

Because they aren't aware that it's there or of its dangers

[arcticbull]

It's mostly inert and generally recognized as safe. It's also on the ingredients list, and even the EU allows it, as additive E900. Last re-evaluated in 2020.

[1] https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa...